JPS6143294A - Vertical shaft pump - Google Patents

Abstract

PURPOSE:To stabilize vertical movement of the pump in the caption, by supporting the outer race of a bearing carrying the rotary shaft of a vertical shaft pump by means of a support member which supports said outer race movably in axial direction but restricts it in turning direction. CONSTITUTION:The ball bearing 10 of a vertical shaft pump is fitted on a rotary shaft 2 and its inner race is fixed to the rotary shaft 2 by means of shaft sleeves 16a and 16b. A gap of driven size is provided between the outer race of ball bearing 10 and a fixed support member 17 and the outer race of ball bearing 10 is movable in axial direction but its turn in turning direction is restricted by means of a pin-shaped shaft 19. Accordingly, a balance disc is fixed and vertically moving rotary shaft can be supported steadily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a vertical shaft pump that stably supports a rotating shaft provided with a thrust disk that is freely movable in the axial direction.

[Background of the invention]

A conventional vertical shaft pump of this type will be explained with reference to FIG.

In the figure, 1 is the final stage impeller fixed to the rotating shaft 2, 3 is a balance disk also fixed to the rotating shaft 2, and a fixed M4 facing this balance disk 3 and extending from the casing reduces thrust. configuring the device. 5
is the high pressure impeller back pressure chamber, 6 is the narrow gap, 7 is the balance chamber pressure chamber, 8 is the low pressure balance disk back pressure chamber, 9
consists of a motor rotor 9a and a motor stator 9b.

Ball bearings 10a and 10b support the rotating shaft 2, and are supported by fixed walls 4a and 4b extending from the casing. 11
A suction pipe 12 is provided in the outer casing.

13 is a return pipe that returns the fluid after cooling the motor 9 and the bearings 10a, 10b to the suction side of the impeller; 14 is a discharge pipe; and 15 is a discharge passage connected to the discharge pipe 14. Note that 2a is a groove bored in the rotating shaft 2.

In the above configuration, most of the fluid flowing in from the suction pipe 12 due to the rotation of the impeller is sent to a predetermined location via the discharge pipe 14 and the discharge passage 15. A part of this discharged water passes through the impeller pressure chamber 5, passes through the narrow gap 6, balance disk pressure chamber 7, bearing 10b, balance disk back pressure chamber 8, returns to the return pipe 13, and passes through the groove 2a to the bearing 10a and motor 9. is cooled and returned to the suction side of the pump via the return pipe 13. In this state, the shaft thrust acting on the impeller 1 causes the rotating shaft 2 to
When the balance disk pressure chamber 7 moves upward in the figure, the balance disk pressure chamber 7 is pinched, the fluid flow resistance in this area increases, the pressure drop in the narrow gap 6 decreases, and the pressure in the balance disk pressure chamber 7 increases. Therefore, a downward force is generated in the balance disk 3, which acts to push the rotary shaft 2 back downward.

For this reason, the bearings 10a, 10b and the fixed wall 4a.

4b, it is essential to provide a gap necessary for the vertical movement of the rotating shaft 2, but if this gap is too wide, the bearing 1
There is a problem in that the outer rings 0a and 10b rotate together with the rotating shaft 2 and no longer function as bearings.

On the other hand, if the gap is too narrow, the bearing 10a.

The outer ring of the rotary shaft 10b is fixed to the fixed walls 4a and 4b, resulting in a problem that the vertical movement of the rotary shaft 2 is hindered. Furthermore, even if this gap is set optimally when it is stationary, there is a problem that shaft vibration or oblique movement of the shaft may cause the shaft to jam and prevent the vertical movement of the rotating shaft 2, making it extremely difficult to set this gap. . A method for avoiding this problem is disclosed in Japanese Patent Application Laid-Open No. 10796/1983.

This is constructed by installing a hydrostatic bearing on the outer ring of a ball bearing that supports the rotating shaft.This makes it easy to move the rotating shaft up and down, and provides sufficient support in the radial direction of the ball bearing. It will be done. In particular, when the rotary shaft 2 is in operation, the static pressure bearing functions, and when the rotary shaft 2 is stopped, the function of the ball bearings provides the effect of completely supporting the rotary shaft. However, there is a problem in that the structure for introducing pressurized liquid to make the hydrostatic bearing function becomes complicated.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a chamber shaft pump having a fixed balance disk and supporting a rotary shaft that moves up and down to stabilize its up and down movement.

[Train of invention]

The present invention achieves the above object by supporting an outer ring of a bearing that supports a rotating shaft by a support member that is movable in the axial direction and restrained in the rotational direction.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 8.

In the figure, the same parts as in FIG. 9 are denoted by the same reference numerals.

FIG. 1 shows a first embodiment of the invention.

A motor rotor (not shown) constituting a motor, a balance disk (not shown) constituting a thrust balance device, and an impeller (not shown) are fixed to the rotating shaft 2.

Ball bearings 10 are placed on both sides of the motor rotor. Although only one side of the motor rotor will be described here, the other side has the same configuration. This ball bearing 10 is arranged on the rotating shaft 2. The inner ring is fixed to the rotating shaft 2 by the shaft sleeves 16a and 16b. A predetermined gap a is provided between the outer ring of the ball bearing 10 and the fixed support member 17. Further, a small hole 18 is formed in the outer ring in the axial direction, and is configured to play with a pin-shaped shaft 19 provided on the support member 17. As a result, the outer ring of the ball bearing 10 can freely move in the axial direction, but its rotation in the rotational direction is restricted by the pin-shaped shaft 19.

2 to 7 show a second embodiment of the present invention,
A holding member is arranged on the opposing surface of the outer shaft of the ball bearing 10 and the support member 17, and is constructed to stabilize shaft support based on vertical movement of the shaft.

The holding member in the case of FIG. 2 is constructed by arranging an O-ring 20 on a support member 17 facing the outer ring of the ball bearing 10.

The holding member in the case of FIG. 3 is constructed by arranging a piston ring 21 in place of the second O-ring 20.

The holding member in the case of FIG. 4 is constructed by disposing repulsive magnets 22a and 22b on the above-mentioned opposing surfaces.

The holding member in the case of FIG. 5 is constructed by arranging spring members 23 in a staggered configuration.

The holding member in the case of FIGS. 6 and 7 has a curved or bent surface formed on the outer ring of the ball bearing 10 or the support member 17 facing the outer shaft, and the gap between the opposing surfaces is in contact with or at one point in the axial direction. They are configured to face each other.

FIG. 8 shows a third embodiment of the present invention.

Small hole 18 provided in the outer ring of the first embodiment, pin-shaped shaft 19
In place of the combination with the first embodiment, a key groove 24a is cut into the outer ring of the ball bearing 10, and the support member facing the key groove 24a is configured as a key 24b, and the effect is almost the same as that of the first embodiment. Can be done.

〔Effect of the invention〕

As explained above, according to the present invention, the outer ring of a ball bearing is supported by a support member that allows free movement in the axial direction and restrains it in the rotational direction, and stably supports the rotating shaft that moves up and down. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the main part of the first embodiment of the present invention.
FIG. 7 is a sectional view of a main part of a second embodiment of the invention, FIG. 8 is a sectional view of a main part of a third embodiment of the invention, and FIG. 9 is a sectional view of a conventional chamber shaft pump. . DESCRIPTION OF SYMBOLS 1... Impeller, 2... Rotating shaft, 3... Balance disk, 4... Fixed wall, 10... Ball bearing, 17...
- Support member, 19... Pin-shaped shaft, 20... O-ring, 21... Piston ring, 22a, 22b...
Magnet, 23... Spring member, 24b... Key. Aku 1 cause Kaya 2 Snake ♀ 30 th + Menkan 5th eye 114 figure ￥ｑ口′＃′１ Snake

Claims (1)

[Claims] 1. A rotor fixed to a rotating shaft, a motor stator disposed in a casing facing the motor rotor with a predetermined gap therebetween, and a rotor fixed to the rotating shaft. A ball bearing is rotatably supported at the upper and lower parts, an impeller is fixed to the rotating shaft and rotates together with the rotating shaft and discharges liquid upward, and the impeller is disposed between the impeller and the bearing on the lower side. A vertical shaft pump equipped with a thrust reduction device for reducing shaft thrust generated during operation, characterized in that the outer ring of the bearing is supported by a support member that allows free movement in the axial direction and restrains it in the rotational direction. 2. In claim 1, the support member includes an opening formed in the axial direction of the bearing outer ring, and a pin-shaped shaft that fits into the opening so as to be freely movable in the axial direction and restrains in the rotational direction. A vertical shaft pump characterized by: 3. In claim 1, the support member includes a holding member that holds the bearing outer ring, an opening bored in the axial direction of the holding member, and a rotatable member that is fitted into the opening so as to be freely movable in the axial direction. A vertical shaft pump characterized by consisting of a pin-shaped shaft that restrains the direction.